TY - JOUR
T1 - Hexagonal boron nitride thin film thermal neutron detectors with high energy resolution of the reaction products
AU - Doan, T. C.
AU - Majety, S.
AU - Grenadier, S.
AU - Li, J.
AU - Lin, J. Y.
AU - Jiang, H. X.
N1 - Funding Information:
The efforts on h-BN material growth and neutron detector fabrication are supported by DHS ARI Program (No. 2011-DN-077-ARI048), the studies of the fundamental optical and transport properties of h-BN are supported by DOE (DE-FG02-09ER46552), and the studies of the basic structural properties of h-BN are supported by NSF (DMR-1206652). Jiang and Lin are grateful to the AT&T Foundation for the support of Ed Whitacre and Linda Whitacre Endowed chairs.
Publisher Copyright:
© 2015 Elsevier B.V.
PY - 2015/5/21
Y1 - 2015/5/21
N2 - Hexagonal boron nitride (h-BN) is highly promising for solid-state thermal neutron detector applications due to its many outstanding physical properties, especially its very large thermal neutron capture cross-section (~3840 barns for 10B), which is several orders of magnitude larger than those of most other isotopes. The focus of the present work is to carry out studies on h-BN thin film and detector properties to lay the foundation for the development of a direct-conversion solid-state thermal neutron detector with high sensitivity. The measured carrier mobility-lifetime (μτ) product of h-BN thin films grown on sapphire substrates is 2.83×10-7 cm2/V for electrons and holes, which is comparable to the value of about 10-7 cm2/V for GaN thin films grown on sapphire. Detectors based on h-BN thin films were fabricated and the nuclear reaction product pulse height spectra were measured. Under a bias of 20 V, very narrow individual peaks corresponding to the reaction product energies of α and Li particles as well as the sum peaks have been clearly resolved in the pulse height spectrum for the first time by a B-based direct-conversion semiconductor neutron detector. Our results indicate that h-BN thin film detectors possess unique advantages including small size, low weight, portability, low voltage operation and high energy resolution of specific reaction products.
AB - Hexagonal boron nitride (h-BN) is highly promising for solid-state thermal neutron detector applications due to its many outstanding physical properties, especially its very large thermal neutron capture cross-section (~3840 barns for 10B), which is several orders of magnitude larger than those of most other isotopes. The focus of the present work is to carry out studies on h-BN thin film and detector properties to lay the foundation for the development of a direct-conversion solid-state thermal neutron detector with high sensitivity. The measured carrier mobility-lifetime (μτ) product of h-BN thin films grown on sapphire substrates is 2.83×10-7 cm2/V for electrons and holes, which is comparable to the value of about 10-7 cm2/V for GaN thin films grown on sapphire. Detectors based on h-BN thin films were fabricated and the nuclear reaction product pulse height spectra were measured. Under a bias of 20 V, very narrow individual peaks corresponding to the reaction product energies of α and Li particles as well as the sum peaks have been clearly resolved in the pulse height spectrum for the first time by a B-based direct-conversion semiconductor neutron detector. Our results indicate that h-BN thin film detectors possess unique advantages including small size, low weight, portability, low voltage operation and high energy resolution of specific reaction products.
KW - Hexagonal boron nitride
KW - MOCVD growth
KW - Semiconductor thin film detectors
KW - Solid-state neutron detector
UR - http://www.scopus.com/inward/record.url?scp=84924692272&partnerID=8YFLogxK
U2 - 10.1016/j.nima.2015.02.045
DO - 10.1016/j.nima.2015.02.045
M3 - Article
AN - SCOPUS:84924692272
VL - 783
SP - 121
EP - 127
JO - Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
JF - Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
SN - 0168-9002
ER -